Introduction
Acquisition of peak bone mineral mass, essential to bone health in adults, occurs during late childhood, adolescence and early adult life. This process can be disturbed by numerous factors including diet, disease, treatment and lifestyle.¹ Such perturbation is well described in children and adolescents with acute lymphoblastic leukemia (ALL) before, during and after therapy.² Important contributors to the outcome, osteopenia, are corticosteroids and methotrexate²׳3 which are part of all treatment regimens for this disease. The most common method for determining bone mineral density (BMD) is dual energy X-ray absorptiometry (DXA) focused on the lumbar spine (LS). A limitation of DXA is the provision of two-dimensional measurement, so providing areal (a) BMD. Peripheral quantitative computed tomography (pQCT) allows the determination of volumetric (v) BMD, separate assessment of cortical and trabecular bone (not possible with DXA), and portability. In the overall study of bone health and body composition of long term survivors of ALL in early life,⁴ pQCT was undertaken in addition to DXA to enable a comprehensive evaluation of bone geometry, density and strength.⁵ The purpose was to improve understanding of the mechanisms resulting in enhanced risk of fracture and an element of the frailty syndrome which are well recognized in these survivors.⁶ This report describes the pQCT component of the study. Such insights relating to bone structure should also inform strategies for amelioration and even prevention of osteopenia and its attendant morbidity.